17 February, 2023
How do we view plants in the real world?
Are plants as advanced (> or =) as humans?
Plants pull all of this off while…
Plants as sessile organisms
- Mostly defined by their total inability to move
- Is this a good thing or a bad thing?
- Their Darwinian struggle for growth, survival and reproduction in very different arenas has resulted in an extremely wide variety of form and function (Diaz et al 2016)
Themes in vascular plant form
- Plants extract materials from environment
- ~18 essential elements
- soil (most)
- atmosphere (a few)
- materials can be limiting
- Above- and belowground body plan
- connected via vascular tissues
Themes in vascular plant form
- Plants extract materials from environment
- ~18 essential elements
- soil (most)
- atmosphere
- many materials are limited
- Above- and belowground body plan
- connected via vascular tissues
- Plants exhibit indeterminate growth
- “foragers”
- diversity of sizes & shapes
- BRAINSTORM: What factors drive change in plant form?
Diversity in plant form via resource uptake vs support
Diversity in plant form via evolutionary history
Diversity in plant form via environment (e.g., climate)
Plants adapt form to persist in different environments
Plants have 3 tissue systems connecting all plant organs
How do plants create such dynamic structures? Cells!
Parenchyma cells: living, dividing with metabolic function
Parenchyma cells in leaves = Mesophyll cells Contain chloroplast and carry out photosynthesis
Collenchyma (flexible) & Sclerenchyma (rigid) for support
Vascular tissues: Xylem composed of water conducting cells
Vascular tissues: Phloem composed of sugar conducting cells
Dynamic root growth integral for plant function
Root morphology is super diverse
Roots are a member of a living soil community
Roots supply nutrients & water for growth & metabolism
Plant growth occurs through meristems
Cambium produce secondary growth (out not up)
